The four of them piled into the launch. An engineer leaped down and twisted the motor. The fast launch shot forward, the submarine siren at the bow sending out its strange water sound that was inaudible to those on board, but which had such an amazing effect on the microscopic animals that composed the silver sea. As the launch gathered speed and headed up the Hudson a high bow wave spread out on either side. The water on which they rode was yellowed and malodorous, but it was water, and not the silvery, slime that had threatened the world. The Silver Menace vanished before the launch as if by magic. When the motor boat approached, with its siren still sounding fiercely, though inaudibly, the jellied surface of the river shivered into yellowed liquid, and the creeping horror on the banks trembled and became a torrent of water that flowed eagerly back into the bed of the stream. The island on which Morrison had been marooned loomed up ahead, looking like a small mountain of silver. The house at its top was as a monument of shining metal. But as the boat sped toward it the silvery appearance of the coating clouded and melted away. Instead a torrent of evil-smelling water poured down the sloping sides of the island and into the river again! They found the servants weeping for joy. Morrison, when the windows of the library had broken in under the weight of the mass of the horror outside, had leaped through the door of the library and slammed the door behind him. They had calked the cracks with cloth, and for a moment isolated the Silver Menace in that one room. As window after window broke in, however, they had been forced to withdraw from room to room, until at last they were huddled together in a tiny linen closet, windowless and without ventilation. They were waiting there for death when they heard the rushing of water all about them and found the Silver Menace, silver and a menace no longer, flowing down to rejoin the waters from which it had come. As is the way of women, Nita, having sobbed heartbrokenly for sorrow when she believed her father dead, now sobbed even more heartbrokenly for joy at finding him alive, but she did not neglect, after a reasonable interval, to bring Davis forward. "You know him, daddy," she said, smiling. "Well, he is the person who found the way to destroy the Silver Menace, and so he's the person you are going to pay that big reward to." Morrison shook hands with Davis. He knew what was coming next. "And though it hasn't anything to do with the other things," Nita said proudly, "he's the person I'm going to marry." "It would be ungracious," observed Morrison, "to disagree with you. Mr. Davis, you are a lucky man." "I know it," said Davis, laughing in some embarrassment. He looked at Nita, who dimpled at him, and was promptly and frankly kissed for her daring. She did not seem to mind, however. In fact, she dimpled again. * * * * *